Piston construction



April 10, 1928.

w. c. BROWER PISTON CONSTRUCTION Filed Nov. 18, 1925 u INVZZTOR.

Patented Apr. 10, 1928.

UNITED STA WILLIAM. C. BROWER, 0F GLOVERSVILLE, NEW YORK.

PISTON cons'rnucrroim- Application filed November 18, 1925. Serial No. 69,742.'

This invention relates to improvements in piston constructions and the object of the invention is the provision of a piston for internal combustion engines such as used for the propulsion of. automobiles, motor vehicles and the like in which the pumping of the lubricating oil past the piston is prevented, which results in the increased etliciency in the engine, diminution in the matter of the formation of carbon on the iston head, prevention of loss of lubricating oil and other advantages obvious to those skilled in the art. i

It is well known that in the operation of these internal combustion engines on the down stroke of the piston the lubricating oil, which is on the wall of the cylinder and on the outer surface, rings and in the ring grooves of the piston, is drawn or forced upwardly into the cylinder above the piston head dueto the fact. that a vacuum or partial vacuum is created there by the down stroke of the piston, and the crank-case pressure thus forces this lubricating oil up along the parts above referred to. Of course, it is understood that a quantity of the oil is held in the grooves for the rings and that this is forced by this pressure upwardly into the space in the cylinder above the piston head. This is called oil pumping, and it is .the purpose of this invention to eliminate this objectionable action. v To the accomplishment of the foregoing and such .other objects as may hereinafter appear, this invention consists in the construction, combination and arrangement of parts hereinafter described and then sought.

to be defined in the appended claims, ref-' erence being had to the accompanying drawings forming a part hereof and which show for the purpose of illustrative disclosure'two embodiments of my invention, it being expressly understood, however, that various changes may be made in practice within thescope of theclaims-without digressm'g from my inventive idea.

' In the drawings Figure 1 represents a view in side elevation-and partial vertical cross section of a piston constructed to-embody my invention;

Figure 2 is a fragliie tary view showing a slight modification in the structure, which also embodies my invention.

In the drawings, the numeral 1 designates a piston. head, t-he general construction of which is standard, it being understood thatlinstance holes or aperi provided, (see Figures 1 and 2) I provide a plurality of holes or apertures 4 openin from the bottom of the groove into the hollow interior or inside of the piston head.

In the construction shown in Figure 1 I i provide these holes or apertures 4 in they lower two. grooves, whereas in the construction shown in Figure 2 I provide these holes or apertures in the lower groove only. In the annular wall or rib 3 located just above the upper groove 2 having the holes or apertures 4 therein,'I provide a. plurality of holes or apertures 5 .whieli'extend from the outer face ofvthis wall or rib through the same and open into the hollow interior of the piston head 1. In additon, I reduce the outer face of the upper portion of this annular wall or rib having the holes or apertures 5 therethrough to form a depressed surface 6 and a medial shoulder 7. The holes or apertures 5 open partly'tli'rough the depressed portion. 6v and partly through the other portion of this wall or rib 3. In the form shown in Figure 1' the wall or rib 3 having the holes or apertures 5 is the second ,one (3 from the bottom, Whereas in the construction shown in Figure 2 it is the first one from, the bottom (3 In operation, on the downward stroke of the piston within the. cylinde; the piston rings and particularly the lowermost rings .8-and.,;9 will remove the surplus lubricating oil from the inner surface of the piston and part of it will enter the lowermost grooves 2 and2. -In ordinary constructions this oil would be subject to the crank-case .pressure due to the reduction in pressure in the cylinder because of thedownward movement of thepiston. However, when the pressure 7 in the cylinder above-the piston is reduced or a partial vacuum iscreated', the crankcase pressure'is through the holes or apertures 5in-thewall' or rib, 3 in'tho one instance (Figure "1) and.3 .,in the other turns 5 afiord means of communication between the part of the cylinder above the wall or rib 3 and 3 as the case may be, and the crank-case pressure whereby the usual pressure tending to force the coil which is' collected in the grooves 2 and 2 upwardly is neutralized or balanced and, therefore,

' the oil is free to flow by gravit through the holes or apertures 4 back into t e crank-case. The reduction in the upper part of the face of'the wall or rib 3 and 3 provides sufficient space for the admission of suflicient air pressure from' the crank-case into the cylinder between the wall of the cylinder wall of the piston and opening into the hol-' low interior thereof, one of the walls or ribs and the upper part of the outer face of the -piston to accomplish this purpose regardless above said last-mentioned. groove being provided with a pluralityof openings therethrough leading from the outer face thereof to the interior of the hollow piston so as to aflord means of communication between the cylinder and theerank-case, said wall or rib having a reduced portion and the openings extending through both the reduced POIfiiOII and the main portion of this rib or wa 2. In combination, a hollow having a plurality of piston ring g rooves formed therein with a plurality of annular ribs or walls provided between said grooves,

a plurality o passages between the interior of the piston head and the two lowermost of the 'said grooves, said passages opening into the bottom of said grooves and being adapted for the passage of lubricating oil from the grooves into. the interior of the piston head,

and a plurality of passages between the in-- terior of the piston head and the outer surface of the annular rib or wall immediately above the two lowermost grooves, said passages opening through the outer face of said rib or wall whereby .a means of communication is provided between the crank-caseand the spacebetween the 11 per part of the piston head' and the cylin er in which"the pispiston head a ton is adapted to be mounted, said rib or wall havingasaiidnreduced lilon;I p h f testimonytatcimteo ing I'have hereunto set my hand this l tfi day of October, 1925,

WILLIAM o. Browse,

portion of its surface reduced and said openings being located in part in 

